Shoe making

ABSTRACT

Methods and apparatus for making shaped upper components for a shoe, Whole upper components or upper part upper components can be made. Vacuum and pressure forming techniques for conforming initially flat material to a moulding surface are disclosed. The moulding surfaces may be of a shape whereby the preformed upper is convertible to the shape of the last merely by a bending operation. The mould shape can be arrived at by forming a sheet of resiliently bendable material such as unplasticized PVC to the last shape required to form a shell and, after removing the shell from the last, partially flattening it by spreading outwardly the opposite sides. Where a male mould is used the surface of the material which is to be the outside surface of the shoe can be in contact with the mould surface, and the preformed upper would be turned inside out after removal from the mold; where a female mould is used the surface of the material which is to be inside the shoe may be in contact with the moulding surface and again the preformed upper would be turned inside out after removal from the mould. The moulding surface may be embossed to transfer a pattern to the upper material. The material is held during the moulding operation. A device for partially cutting out the upper from the sheet of material from which it is formed may be provided, which device may also operate as a clamp for holding the material during the forming operation.

United States Patent 1 Wyness et al.

[ SHOE MAKING [75] Inventors: Keith Gordon Wyness; Alan Roy Dodd, bothof Norfolk; John Nigel Dixon Spinks, London; Kevin David NicholasKearney, Woking, all of England [73] Assignee: The Shoe and AlliedTrades Research Associated, Kettering, Northamptonshire, England [22]Filed: Nov. 18, 1970 [21] Appl.No.: 90,770

[30] Foreign Application Priority Data Nov. 20, 1969 Great Britain..56,929/69 [52] U.S. Cl. ..l2/146 C [51] Int. Cl. ..A43d

[58] Field of Search ..l2/146 R, 146 C [56] References Cited UNITEDSTATES PATENTS 3,445,873 5/1969 Staden ..l2/l46C 2,540,850 2/1951 Walsh....l2/l46C 2,666,935 l/l954 Gilbert et al..... ....l2/l46 C 3,309,7253/1967 Staden ..l2/l46C Primary ExaminerPatrick D. LawsonAttorney-Lemer, David & Littenberg 1March 20, 1973 5 7 ABSTRACT Methodsand apparatus for making shaped upper components for a shoe, Whole uppercomponents or upper part upper components can be made. Vacuum andpressure forming techniques for conforming initially flat material to amoulding surface are disclosed. The moulding surfaces may be of a shapewhereby the preformed upper is convertible to the shape of the lastmerely by a bending operation. The mould shape can be arrived at byforming a sheet of resiliently bendable material such as unplasticizedPVC to the last shape required to form a shell and, after removing theshell from the last, partially flattening it by spreading outwardly theopposite sides. Where a male mould is used the surface of the materialwhich is to be the outside surface of the shoe can be in contact withthe mould surface, and the preformed upper would be turned inside outafter removal from the mold; where a female mould is used the surface ofthe material which is to be inside the shoe may be in contact with themoulding surface and again the prefonned upper would be turned insideout after removal from the mould. The moulding surface may be embossedto transfer a pattern to the upper material. The material is held duringthe moulding operation. A device for partially cutting out the upperfrom the sheet of material from which it is formed may be provided,which device may also operate as a clamp for holding the material duringthe forming operation.

18 Claims, 19 Drawing Figures PATENIEDMARZOIHY?) f 3.720.971

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PAIENIEDMARZO ms 3. 720,971

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PATENIEDMARZO 1975 3,720,971 SHEET 05 OF 10 PATENTEDMARZO I975 SHEETO80F 1O FI G17.

SHOE MAKING This invention relates to shoe making and'is concernedparticularly with the production of shaped shoe uppers and shoe uppercomponents. The invention provides novel methods and apparatus forproducing such articles. The term shoe is used herein broadly and isintended to cover any article of footwear.

In shoe making, it is necessary to deform the material from which the,upper of the shoe is made from its initial flat condition so that isassumes the required shape. Conventionally, this deformation has beencarried out on a last and requires high operator skill and/orcomplicated machinery to stretch and compress thematerial to itsrequired shape. I

We have proposed methods and techniques for simplifying the formation ofuppers by preshaping the upper forepart component so that the stretchingand compression is carried out separately from the operation of bendingor wrapping the material into a last shape.

Our British Patents Nos. 1096001 and 1096002 describe methods fordetermining the amount of stretch required in the material and forputting this stretch into the material by a mechanical gripping andpulling operation before conforming the material to the last.

Our British Patent Specification Nos. 1102695 and 1102696 describemethod and apparatus for carrying out the preshaping operation on upperforeparts using male moulds. The shape of the moulds is that which wouldbe arrived at by forming ,a sheet of resiliently bendable material, suchas unplasticized polyvinyl chloride, to the last shape required andpartially flattening out the shell by outwardly displacing the sideportions.

U.S. Pat. No. 3,64l,603 also describes mechanical methods and apparatusfor conforming the material to the mould.

The methods described may be useful both with natural and with syntheticupper materials e.g., leather, poromeric material or PVC.

Such upper materials conventionally have one side, which is known as thegrain side, intended to form the outer surface of the upper and anopposite side, known as the flesh side, intended to form the innersurface of the upper. in the methods referred to, the flesh side of thematerial is presented to the surface of the mould.

The present invention has as one object the provision of a novel andimproved method of preforming shoe uppers and shoe upper components.

Another object is the provision of an improved method of makingpreformed'shoe uppers and shoe upper components having a characterizedor patterned outer surface in the finished shoe.

According to one aspect of the present invention a method of making ashaped upper component for a shoe which comprises deformation of a flatsheet material to a shoe upper shape is characterized in that the sheetmaterial is deformed by being conformed to a moulding surface having apreformed shape for said component, said preformed shape being such thatsaid upper component is convertible from the preformed shape to a shoeupper shape essentially merely by bending, and is thereafter convertedto the shoe upper shape essentially by bending and in that the sheet isheld during the formation whereby thedeformation involves stretching ofthe sheet material and in that the shaped upper component is turnedinside out prior to assembly into the shoe.

Moulds having moulding surfaces of the preformed shape referred to abovemay be devised as disclosed in British Patent Specification Nos. 1102695and 1102696 and in the specifications filed in the above mentionedapplications, the disclosures of which are incorporated herein byreference. The preformed shape preferably includes the vamp and is suchthat in the region of the vamp point the distance between two points atthe feather edge on opposite sides of the longitudinal axis of thepreformed shape is not more than about 35 percent greater when measuredalong the surfaces of the preformed shape than when measured along astraight line between the two points, both measure ments being alonglines at right angles to the longitudinal axis of the preformed shape.

Preferably the first mentioned distance is about 10 percent greater thanthe second mentioned distance. However, the distance can be chosen.according to the material with which the mould is to be used, thecriterion being to avoid stretching of the material to such an extentthat undesirable effects such as excessive thinning occurs.

One advantage which may be achieved by this aspect of the invention isthat when the deformed material is turned inside out the outer layer ofthe material ie at the grain surface side is stretched andthis mayreduce the tendency to wrinkling in the subsequently assembled upper inthe shoe.

In one form of this aspect of the invention the sheet material isconformed to a female mould and the surface of the sheet which will beinside the shoe is presented to the mould. This provides the advantagethat where no embossing is required, the grain surface of the materialremains unmarred by the forming operation.

It will be appreciated that a left hand preformed shape will produce aright hand shoe after the preformed shoe component has been turnedinside out, and vice versa.

The term shoe upper component includes both a complete shoe upper andparts of a shoe upper, such as a vamp or forepart or a quarter or heelor back part, which will need assembly with other components to form thecomplete upper.

The invention can be used with material in the form of blanks which havebeen precut to the required shape, from the original sheet material, andwith sheet material which is first moulded and thereafter at some stage,the upper which is preformed in the moulding step is cut from the sheet.

The deformation of the upper material to the preformed shape can becarried out by any suitable method for example pressure differentialmethods such as vacuum forming or pressure forming to a male or femalemould or by mechanical methods eg. by pressing a male mould into aclamped sheet of the material or any combination of these methods.

The use of super atmospheric pressures has a number of advantagesespecially in connection with male and female moulds and is preferred.

Such pressure may, if desired, be applied through a diaphragm or by aflexible bag, for example, or can be applied without these aids.

The air may be vacated from between the mould and the sheet by theapplication of a slight subatmospheric pressure to the mould side of thesheet or valves opening in response to rises in pressure may be providedto vent the air through the moulds. Such vents or valves canconveniently be located in the area which eventually will be cut outfrom the shaped material to provide the ankle opening in the shoe.

Where a synthetic upper material for example a thermoplastic material isused, it is preferably preheated before being conformed to the mould andthe mould is preferably cold. Where leather is used, it is preferablethat the mould itself be heated, and the leather is pretreated as by theapplication of heat and moisture, to

' make it soft.

It will be appreciated that in general the deforming pressure will beapplied to the sheet material whilst it is either heated or wet withmoisture or an extending agent and that the deforming pressure will bemaintained whilst the material is cooled or dried.

The treatments are such that if the material was water vapor permeablebefore the deformation treatment it is still water vapor permeable afterthe deformation. Thus the preferred microporous unreinforcedpolyurethane sheets typically have, collapse temperatures in the range170 190C ie when heated for say minutes at these temperatures in aconvection air heated oven they lose their porous structure and becometranslucent.

Clearly the heat treatments or liquid treatments are not such as tocause collapse of the material, i.e. the temperatures used are wellbelow the melting temperatures of the polymers.

The preformed upper component is assembled to form a complete upper bentto the desired upper shape for example by wrapping round a last or shoeshape, being detached from the remainder of the sheet before this stepand at least an out sole attached for example by injection moulding.

The preformed shape can be an accurate finished shoe upper shape apartfrom the bending or can be an oversize shape and could be allowed orcaused to shrink to fit back onto a last or mould as by suitable heattreatment.

The reference to fluid pressure above includes it will be appreciatedboth gaseous or air pressure as well as fluid pressure applied byliquids.

If desired these fluids may be heated or heat may be separately appliedfor example by radiation or by dielectric heating.

The fluids may be inert to the extensible material or may be such as toenhance the materials extensibility for example moist air or steam couldbe used. Alternatively with homogeneous microporous thermoplastic sheetmaterials for example made of polyurethanes organic liquids such asacetone.

It was mentioned above that the conditions are such as to achieve atleast temporary deformation whereby the material adopts a preformedshape which can be converted to a shoe upper shape essentially'merely bybending. The permanency of the deformation need only be sufficient toachieve the object of the present invention namely that the deformedsheet can be converted to an actual shoe shape merely by being appliedto and wrapped round a last or former or merely bent essentiallyrequiring only a bending of the upper 5 without the need for anysignificant further stretching of the material. Once the material is ona last and is held by the last in the shoe upper shape conventionalsetting techniques can be used to build in the strains or extensionsintroduced in the deformation step so that they are retained on a morepermanent bases e.g. in temperate conditions for months, or even years.Desirably the initial deformation is such as to actually achieve asubstantially permanent deformation in this sense with little or nosetting being required on a last.

Such conventional setting techniques involve holding the material on thelast for extended periods e.g. up to a month, dry heat treatment, e.g.exposures to dry air at 140C on the last for a number of minutes, ormoist heat treatment e.g. moist heated air or steam for similar orshorter periods.

An in situ reinforcing top line tape could be inserted in this part ofthe sheet material, prior to deformation. The moulds themselves may bemade of porous rigid material to facilitate this e.g. being made ofsintered high density polyethylene powder which material in one-eighthinch thickness can readily be moulded but which on cooling is a strongrigid material providing quite smooth surfaces.

A surface finish either plating to impart a smooth or patent finishingor embossing to provide a grained or other skln or patterned finish canbe achieved simultaneously with the deformation step for example whenusing female moulds with the flesh surface of the material facing themould. Thus if desired an em bossing or plating means can be placed ontop of the material so that embossing of the grain surface takes placeduring the forming operation. Such embossing means might be, forexample, a diaphragm having an embossing surface or might be a flexiblebag having an embossing surface, which bag might also be used forapplying the pressure if pressure forming is carried out. Thus the useof embossing means can be especially advantageous as it will assist inthe forcing of the material into the mould. Details of such means aregiven in the US. application Ser. No. 46,751, filed June 16, 1970.

Alternatively a suitably smooth or patterned or crumpled heat conductingsheet e.g. of metal foil e.g. 0.001 to 0.020 inches thick, such asaluminum foil can be used as taught in French Patent Specification No.1598244 the disclosure of which is incorporated herein by reference.Relatively high short duration temperatures are preferred and thesecould be induced in the surface in contact with the coil either byconduction by providing resistance heaters in the moulds or by inductionor dielectric heating especially if the surface of the sheet was wettede.g. by wetting the foil prior to the process.

However, where the pattern is to be replicated a large number of times,it is preferred that the mould surface itself is provided with anydesired aesthetic configuration such as to modify the surface appearancee.g. grain skin or emboss finishes or modifications, replicating cuttingconsolidating stitching, punching or inlaying techniques commonly usedin shoe manufacture. Thus, the requirement for a separate embossingmeans is avoided.

Where the upper material has a grain surface and a flesh surface, as isnormal in shoe upper materials, the surface on which the pattern isformed would normally be the grain surface.

Preferably the edges of the material around the mould are clamped duringthe forming operation,

whether the material be in sheet form or in precut blank form.Peripheral clamping greatly assists in achieving a smooth unwrinkledmoulding. The clamp- 'ing can be conveniently achieved using a clampingmember which co-operates with the surface of the mould which surroundsthe edge of the mould cavity, the clamping member being shaped tocorrespond approximately with the outline or periphery of the mouldingsurface. Thus a female mould having a top surface which surrounds themoulding cavity and acts as one clamping member, simplifies clamping.The other clamping member may be, for example, made of steel strip.

Desirably the material is at least partially cut around the periphery ofthe preformed shape prior to removal from the mould thus avoiding theneed for a subsequent cutting operation. The material is preferably heldby clamping means which may also afford cutting means knife edgeeffective at clamping pressure only to cut the sheet material whenheated and the cutting means are heated after the material has beenconformed to the preformed shape, for a temperature and time suchas toonly partially sever the preformed shape from the sheet so that thepreformed shape can be removed from the mould with the sheet and besubsequently torn from the sheet without itself being damaged.

' Alternative arrangements resulting in clamping during the deformingstep followed by partial and complete cutting can of course be used forexample the knife edge could be blunt and increased pressure alone couldbe used for the cutting step. a

The process can also be used to locate and even adhere additional shoeupper components on or in the deformed sheet during the deformationoperation. Thus toe puffs counter stiffeners, doublets or others linersprovided with heat or pressure activateable adhesives could be locatedin the desired position on the male or female moulds so that during thedeformation process they are pressed against the surface of the sheetwhich will be the interior of the shoe upper. The adhesivesarepreferably chosen to be such that the heat or pressure or botheffectively secure the components to the sheet material.

Control of the process may be facilitated by applying an initially quitehigh deforming pressure as for example in the nature of a pulse e.g. ofat least multiples of s of p.s.i. even at least 10s or multiples of l0sof atmospheres for example as high as 500 p.s.i. or more followed by alower pressure sustained for a longer period of time. This couldeconomize on the use of pressure fluid thus providing productioneconomics.

The invention also extends to apparatus for carrying out the methods ofboth the above aspects of the invention.

The present invention also extends to moulds for use in the methodsandapparatus described above, especially male moulds having an invertedversion of the desired characterization on their surfaces and femalemoulds having substantially smooth moulding surfaces.

The mould may be a female mould provided with a re-entrant portion or amale mould provided with a divergent turn in defining portion so that onturning the preformed shape inside out the turn in portion will faceinwardly and after suitable notching or slitting, will readily wrapround the last with reduced wrinkling and avoiding the need for rubbingor ironing down onto the bottom of the last.

Use of adhesives to attach the outsole without the need for bottomtacking should also be facilitated because the turn inportion will havea reduced tendency to spread, for example during any heat setting step.

The invention may be put into practice in various ways and certainspecific embodiments will be described by way of-example and illustratedwith reference to the accompanying drawings in which:

FIGS. 1 and 2 are respectively upper and lower perspective views of atlast having a shell of resiliently deformable material conformedthereto, for use in deriving a female mould according to the firstembodiment of the invention;

FIG. 3 is a plan view of the shell. after it has been cut and removedfrom the last and flattened to a shape from which a mould is to bederived;

FIG. 4 is a perspective view of a mould according to the first aspect ofthe invention derived from the shell shown in FIG. 3;

FIGS. 5, 6 and 7 and 8 are sections along the lines V-V, VI-VI,VII--VII, VIIIVIII respectively of FIG,4;

FIGS. 9 to 12 illustrate the steps involved in making a male mouldhaving a characterized surface according to a second embodiment of theinvention;

FIG. 13 is a diagrammatic cross sectional elevation of one form ofapparatus suitable for putting the invention into practice using afemale mould with a re-entrant turn in portion;

in portion 252.giving accurate and automatic definition of the featheredge 253;

FIG. 16 is a'diagrammatic cross section on the line 16 16 ofFIGJS;

FIG. 17 is a diagrammatic cross section on the line 17-- 17 ofFlG. 15;

FIG. 18 is a perspective view of a vacuum forming machine for carryingout the method of the invention,

for example a synthetic upper material such as microporous. polyurethanesheet material; and

FIG. 19 is a detail of part of the machine of FIG. 18.

EXAMPLE 1 Female mould with smooth moulding surface Referring to FIG. 1,a last 2 has formed thereon a shell 4 of resiliently bendable material,such as an unplasticized polyvinyl chloride. The shell may be con- Imade in the shell at the back of the heel and the shell is removed fromthe last.

The edges of the shell at the opposite side portions 8A, 8B are thenmoved outwardly so that the shell is flattened. This may conveniently bycarried out by placing the shell on a board. The degree of flattening ispreferably such that, to the rear of the toe area (namely in the regionof the vamp point) the distance between points A and B on the featheredge, measured along the surface of the shell in a direction transverseto the longitudinal median line M--M is not more than 35 percent greaterthan the distance between the two points as measured in a straight linei.e. the direction distance between the points. Preferably the firstdistance is about 10 percent greater than the second. The flattening isalso such that the edge 8 and the edges 10 (corresponding to the cut 10)lie in a single plane.

The mould is then derived from the inside surface of the shell in aconventional manner. During the formation of the mould a surface portionthereof corresponding to the lasting margin is added and is located inthe vertical plane. The lasting margin surface portion of the mould isindicated at 12 in FIG. 4. Also, next to the edges 10 margin portions 14are formed to enable the seaming of the preformed upper at the rear ofthe upper to be carried out.

Thus, it will be seen that the mould includes a surface area 16 definingthe toe region, a surface area 18 deeper than the area 16 and disposedto the rear thereof and defining the vamp or cone portion of the upperand areas '20 defining respectively the side quarter portions of theupper.

The mould has a plurality of bores 22 to enable a vacuum to be formed inthe mould. In FIG. 6 the distance along the surface is. about 25 percentgreater than across the feather edge and in FIG. 7 about 30 percent.

EXAMPLE 2 The female mould described in Example 1 is used in theapparatus described below with reference to FIGS. 18 and 19 to mould apreformed shape from poromeric material preferably a homogeneousmicroporous polyurethane material as sold under the Registered TradeMark PORVAIR (Details of the nature of this material are given inpublished Belgian Patent Specification No. 745132).

Wrinkling of the material as it is formed into the female mould isavoided as the edges of the material are clamped by clamps 506.

After the material has been deformed in the'female mould it is removedfrom the mould and turned inside out. Before or after the turning insideout, the excess material around the edges is removed by any suitablecutting operation so that the edges of the upper now conform to the freeedge of the lasting margin. Thus the preformed upper is formed.

It may be desirable after assembling the preformed upper with theremaining parts of the shoe on a last to carry out a post settingoperation, as by heating in an oven.

EXAMPLE 3 Male mould with a characterized surface Referring to FIG. 9 ashoe upper 102 is located on a last 104. The upper 102 has 'a patternedouter or grain surface, and is of the gusset casual type, having atopposite sides of the vamp or cone portion 106 a vent or slit 108 behindwhich an elastic insert (not shown) is stitched along stitch line 110.The upper 102 is the model according to which shoe uppers are to be madeutilizing the present embodiment of the invention. However as willbecome apparent, the pattern on the surface is an inversion of thepattern required in the shoes to be made.

The-first step in deriving the mould according to this embodiment of theinvention is to vacuum from on to the last 104 with the model upper 102assembled thereon a shell 111 (FIG. 10) of unplasticized polyvinylchloride. The shell 111 is allowed to set, and thus becomes resilientlybendable. The shell 111 is then out along the line 112 which correspondsto the top line of the upper 102 along the line 114 corresponding to thefeather edge of the upper 102, and along a vertical line 115 at the backof the shoe. A

Thereafter the shell 111 is removed from the last and is spread out, bymoving outwardly the feather edge portions at opposite sides, and thuspartially flattened. The spreading out and flattening is to such anextent that the lines 112, 114, 115 all line substantially in the sameplane. The partially flattened shell 111 is attached to a board 116 asshown in FIG. 11 with its edges positioned in contact with the board 116around the edge of an aperture 118 which is formed in the board 116 andis of the outline shape to which the shell 111 has been spread out.

The attachment of the shell 111 to the board .116 can be convenientlyachieved by small pieces of adhesive tape 120 which, as will be seenfrom FIG. 11 are disposed all the way around the aperture 118. As willbe seen from FIG. 11 the inside surface of the shell 111 has formed onit a pattern which corresponds to the pattern on the outer surface ofthe model upper 102, although obviously the pattern on the shell is aninversion .of that. on the model upper 102, and hence correspondsprecisely with the pattern required in the finished shoe.

Next, a male mould, which is shown in FIG. 12 is derived from the insidesurface of the shell 111 as spread out in FIG. 11. The moulding surfaceof this male mould bears a pattern which is an inversion of the patternon the inside of the shell 111 and which is therefore the same as theoriginal pattern on the model upper 102. The mould comprises a toeportion 121a,

vamp or cone portion 12% and side quarter portions 1210. During theformation of the male mould a portion 122, defining a lasting margin, isadded and a portion 124 around the top line is also added to define amargin for the top line.

EXAMPLE 4 The male mould described in Example 3 is used in the apparatusdescribed below with reference to FIGS. 18 and 19 to mould a preformedshape convertible to a shoe upper shape essentially merely by bendingand having a characterized surface.

A template 520 shown in FIG. 19 is used in this example and is placedover the sheet material during the formation and maintenance of thevacuum in the box 502.

The template 520 (FIG. 19) which is rectangular to fit within the clamp506 and contains openings shaped to fit around the moulds 518 with thematerial thereon, is placed over these moulds as shown in FIG. 19. Thistemplate assists in ensuring that the material 514 is pulled down snuglyover the moulds.

The use of the template is particularly advantageous where a number ofuppers are to be formed simultaneously over moulds disposed in a closelyspaced arrangement in the vacuum forming machine.

Next the moulds together with the template and sheet material areremoved from the vacuum forming machine and transferred to a suitablesupport surface for cutting, by any convenient method, the preformeduppers from the sheet material 514. For example, the template can beused as a guide for a knife when cutting out the preformed uppers fromthe sheet 514; or if desired, a grinding operation can be used to severthe preformed uppers from the sheet material, the assembly of thetemplate, moulds and material being inverted and passed under a grindingdevice.

The edges of the preformed upper now correspond precisely to free theedge of the margins of the required upper i.e. the lasting margin etc.

After the preformed uppers have been severed from the sheet material,they are turned inside out so that the grain surface which; is nowpatterned in view of its being conformed to the patterned mouldingsurface of the moulds 518, in accordance with an inversion of thepattern on the-model upper 102 which is as desired.

It may be desirable after assembling the preformed upper with theremaining parts of the shoe on a last to carry out a post settingoperation, as by heating in an oven.

EXAMPLE Female mould with re-entrant turn in portion and characterizedsurface The apparatus shown in FIG. 13 comprises a block 210 defining afemale mould 211 having re-entrant portions 213 at its edges and airvents about 1 mill (0.001 inch) in diameter. The re-entrant portions 213provide a margin for turning in and attachment to an outsole and definea feather edge 214-.

The block 210 is provided with a characterized or patterned surface. Thecharacterized surface may be an integral part of the mould or may beprovided by a silicone elastomer release lining or coating characterizedor embossed to impart a surface pattern, e.g. a grain leatherappearance, to the deformed sheet or decorating shoe features such aspunching or stitching.

The apparatus also comprises a ram or pressure plate 215 movable intoengagement with the top surface 216 of the mould 210. The edges of theram are preferably arranged to provide a gripping or sealing contactwith the top surface 216 and are also preferably provided by or with aknife edge 217 extending right round the edge of the female mould 211.This knife edge may be provided with heating means to facilitateseparation of the deformed portion of the sheet from the remainder ofthe sheet. The plate 215 is also provided with pressure fluid inletmeans 218 connected via suitable valves con trollers and pressure gaugesto a source of superatmospheric pressure fluid (not shown). Additionalclamps 219 may be provided to hold the sheet in position during thedeformation. The plaTe 215 may also be provided with heating means e.g.radiant or dielectric to enable the sheet to be heated to achieve theinitial deformation into contact with the mould and to facilitate anysetting step used to ensure substantially permanent deformation.

In an alternative embodiment (not shown) the top edge 216 of the block10 provides the cutting edge and may either be provided with internalresistance heaters or the co-operating edge or area of the plate 215 maybe provided with heating means.

One mode of operation is to preheat the sheet 20, e.g. a microporouspolyurethane sheet 1.7 mm thick as described below to say to C locate itover the mould bring the pressure plate into sealing engagement, supplyhigh pressure air e.g. at 100 psi. for a few seconds then maintain thesheet in contact with the female mould for a further minute using air ata pressure of 15 to 20 psi. whilst supplying radiant heat from thepressure plate at say 80 to 90C. Pressure is then applied to thepressure plate and the knife edges 17 heated to say to C either to severthe material completely or enable the deformed area merely to be tornfrom the rest of the material.

The characterized surface of the mould may be made in a manner analogousto that described in Example 3.

Also the mould described in this example could be Other methods ofarranging the relationship between the moulds and the superatmosphericpressure fluid can be used.

EXAMPLE 6 The sheets of extensible material may be laid one on top ofthe other and heated as described in Example 5 and then placed in a twopart mould consisting of two female moulds, e.g. each as described forFIG. 13 placed opening to opening. Pressure fluid is then introducedbetween the two sheets: to blow them apart and into the moulds. Thepressure deforming and setting sequence and conditions for example beingas for Example 5. One of the moulds could be provided with a heatedknife edge as for FIG. 13 interrupted at one or more places to allowpassage of a pipe for introducing the pressure fluid between the sheets.

EXAMPLE 7 In a further alternative embodiment the pressure plate 215 inFIG. 13 could be provided with an inflatable enclosure, preferablyshaped to conform to the female mould 211. This economizes on the supplyof pressure fluid.

EXAMPLE 8 As a further alternative the inflatable enclosure could bereplaced by a perforated or porous plug conforming essentially to theshape of the female mould although leaving a significant space therebetween for access of the pressure fluid.

EXAMPLE 9 Female mould with characterized surface Referring to FIG. 14the apparatus comprises a template 230 having a hole 231 correspondinggenerally to the plan area of the shoe upper after deforming. On oneside of the template 230 there is mounted a perforated plug 233 providedwith a plenum chamber 234 fed as was the input 218 in FIG. 13 withsuperatmospheric pressure fluid. This plug has a shoe upper contactingsurface 235 and a turn in contacting surface 236. On the other side ofthe template 230 there is mounted a perforated vented female mould 240provided with a cutting edge 241 and pressure applying means as inconventional clicker presses. The cutting edge is located just outwardlyof the edge of the hole 231 in the template 230 so that sheet material242 can be out between the edge 241 and the template 230. The mould 240has a characterized shoe upper defining surface 243 and a turn indefining surface 244. The surface ischaracterized in the same way asdescribed in Example 5. The plug 233 and the mould 240 are of suchdimensions that the plug can pass through the aperture 231 and thesurfaces 236 and 244 come into sealing and gripping engagement spacedonly by the sheet 242 whilst an adequate space to provide access for thepressure fluid to evenly deform the sheet 242 is still left between thesurfaces 235 and 243.

The sequence of operations is analogous to that described in Example 5.

EXAMPLE Female mould forepart with turn in portion FIGS. 15 to 17 show afemale mould forepart with a re-entrant turn in portion 252 defining thefeather edge 253. FIG. 17 is a section through the region of the vamppoint 254 and the length of the direct line between point 253 and 255 is5.9 units whilst the length measured around the surface 256 is 7.9 unitsi.e. the length along the surface is about 35 percent greater than thatalong the straight line.

In FIG. 16 the length between point 253 and 257 is 7.5 units whilst thataround the surface 256 is 9.0 units i.e. the length along the surface isabout 20 percent greater than that along the straight line.

The surface 256 may be characterized as describe in Example 5.

Vacuum or pressure forming apparatus A preferred form of vacuum orpressure forming apparatus is shown in FIGS. 18 and 19. The vacuumforming machine comprises a container 500 on top of which is mounted avacuum box 502 which contains a vertically reciprocable air permeablesupport member 504. The support member 504 can be reciprocated by amechanism (not shown) located within the container 500 e.g. an airpressure or fluid pressure actuator. A vacuum pump 505 is connected tothe container 500 to evacuate air therefrom as well as from the vacuumbox A rectangular clamp 506 is horizontally reciprocable on rails 508between a position between radiant heaters 510 which are supported, toone side of the vacuum box 502, on legs 512, and a position in registerwith the vacuum box 502. The clamp is for supporting a piece of shoeupper material 514 during the steps of heating the material andconforming it to moulds as hereinbefore described. The reciprocation ofthe clamp 506 is carried out manually, for which purpose a handle 516 isattaehed to the clamp. Latching means (not shown) is provided forsecuring the clamp 506 in air-tight relationship with the vacuum box 502when the clamp is in register with the vacuum box, whereby vacuum can bedeveloped within the vacuum box. The vacuum box contains two moulds 518which may be as described with reference to any of the Examples 1, 3, 5and 10 as illustrated in FIG. 4.

In operation the vacuum pump 505 is operated to develop vacuum in thecontainer 500, from which communication into the vacuum box 502 isnormally interrupted by a suitable valve arrangement. The heaters 510are energized. A piece of poromeric material from which the uppers areto be made is fixed in the clamp 506 with its grain surface lower mostand the clamp located between heaters 510 so that the material 514 isheated and softened preparatory to the forming operation. Thereafter theclamp 506 is moved to its position in register with the vacuum box 502and secured in that position by the aforesaid latching means. Themechanism for reciprocating the support 504 is then operated to raisethe support and force the moulds 518 into the material 514. At the sametime, the aforesaid valve is opened to place the vacuum box incommunication with the container 500 whereby a vacuum is formed in thebox 502.

The extensible material is preferably at least 0.5 mm thick. For use inthe production of footwear the material preferably has a thickness inthe range 0.5 mm to 5 mm and for womens weight shoes in the range 0.8 to1.5 mm preferably 0.8 to 1.1 mm. For mens weight shoes the range ispreferably 1.1 to 2.5 mm especially 1.5 to 1.8 mm.

The material is extensible preferably having an elongation at break ofat least 20 percent. The use of superatmospheric pressures in accordancewith the present invention enables materials of such low extensibilityto be conformed from sheet material to three dimensional configurations.The use of vacuum techniques would either be ineffective to achieve therequired deformation or would require the use of high forming andsetting temperatures which would be liable to have adverse effects onthe water vapor permeable material, for example causing damage to thesurface of the material, degradation of the polymer or initiationthereof, or loss of preformed surface characterization such asembossing.

Thus the extensible material may include fibrous reinforcement forexample in the form of a woven, knitted or non-woven sheet adhered to orembedded in the water vapor permeable thermoplastic material, or in theform of a non-woven felt desirably consolidated as by punching withbarbed needles and impregnated with water vapor permeable thermoplasticpolymer. Such materials may be provided with adhered woven fabricreinforcements or elongated cell sponge or honeycomb-like masking layersor microporous wear resistant surface layers or any combination of thesefour possibilities.

Materials of this type are disclosed in British Patent SpecificationNos. 914711, 914713 and 1002225, the disclosures of which areincorporated herein by reference.

However, as mentioned above, the preferred material is one which doesnot have its extensibility constrained by the pressure of fibrousreinforcement. Especially suitable materials have extensibilities i.e.elongations at break which are in excess of 100 to 150 percent andparticularly are at least multiples of hundreds of per cent e.g. 300 to500 percent or even 700 percent through materials with values in therange 250 to 450 percent or 350 to 400 percent are of particularsuitability.

These materials to make them useful for shoe uppers purposes alsodesirably have ultimate tensile strengths of at least 20 lbs/inchwidth/mm thickness and preferably 25 lbs/inch width and preferably atleast multiples of tens oflbs/inch width/mm thickness.

The materials are preferably water vapor permeable at least to theextent ofhaving a water vapor permeability of at least 100 preferablyatleast S e.g. 900 1,500 or even 2,000 g/ml24hrs.

The preferred microporous polyurethane preferably has an apparentdensity inthe range of about 0.25 to 0.7 grams/cm, more preferably inthe range of about 0.35 to 0.5 grams/cm. Typically the density of thepolyurethane itself is about 1.2: it will therefore be apparent thatinthe neighborhoodof onefourth to one-half of the volume of themicroporous material is air. The sheetpreferably has a percentelongationat break of above 50 percent (e.g..in the range of about 300 to 400percent or more): a tensile strength above 35 Kg/cm (e.g. in the rangeof about 60 to 100); an elastic modulus above 2 Kg/cm (e.g. in the rangeof aboutj4 to 9) and a notch tear strength above 2 (e.g. in.

the range of 3 to Kg permm of thickness. It should permit the passage ofwater vapor; thus its water vapor transmission should beat least 200.g/m'l24 hrs (measured as in ASTM B 96-66, procedure B). Also, it isdesirable that at least the upper surface of the sheet, after suitablefinishing, be resistant to the passage of liquid water, e.g. thefinished sheet should have a hydrostatic head (British Standard 2823) ofabove 100 mm Hg. While the polyurethane itself usually shows a tensionset below 100 percent as previously discussed, the preferred microporouspolyurethane sheets generally recover completely with substantiallynopermanent set (under standard dry conditions at room temperature) afterbeing stretched 100 percent.

sheet All measurements referred to herein are made at room temperature(e.g. 23C) unless the test method specifies otherwise.

It has been assumed in describing the examples above that the materialis a poromeric e.g. a microporous thermoplastic polyurethane. However,the process is equally applicable to other synthetic upper materialswhich may be porous or not such as PVC. The process can also be appliedto forming leather uppers. In this case, the leather would normally becovered by a sheet of impermeable material, preferably rubber whichwould assist in the forming of the vacuum, leather being usuallyrelatively porous. With some leathers it may be desirable to use a pressure forming operation, or a combination; of high pressure on one sideof the leather with vacuum on the other. Also where forming leatheruppers it is desirable to precondition the leather usually by heat andmoisture and to utilize heated moulds for the heating of the material sothat the heating takes place simultane ously with the forming operation.

Further the carrying out of the present invention utilizing pressureforming instead of vacuum forming can be understood by reference to theU.S. application Ser. No. 86,116, filed Nov. 2, 1970.

It will be appreciated that the degree to which the shell 11 isflattened by spreading; out the feather edge portions at opposite sides,in deriving the male mould, is chosen to suit the particular uppermaterial, which is to be used with the mould that is being formed. Thecriterion is that the depth of the mould should not be so great as tocause excessive thinning of the upper material during the mouldingoperation.

Various modifications are possible within the scope of the invention.

Thus, although the invention has been described particularly inconnection with the formation of shoe uppers utilizing sheet materialduring the conforming of the materialto the moulds, it would equally bepossible to pre-cut the sheet material into blanks before the conformingoperation is carried out, for example as described in the aforesaidPatent Nos. 1102695 and 1102696. And the invention is applicable toforming just the forepart or just the backpart of the upper, as well asto forming the whole upper.

Further, although the apparatus shown in FIG. 19 heats the material fromboth sides, it may be found advantageous in some cases to heat from onlyone side.

1 Likewise, other forms of heating such as HF heating inhave to be used.When porous moulds are used these may impart anundesired modification tothe surface of the material. In addition the lower available pressuredifferences may force one touse high temperatures at which a materialhaving a pre-characterized or embossed surface will either lose thisembossing by reason of the plastic memory of the softened material orwill have the pre-characterization flattened out possibly permanently.

The use of superatmospheric pressures enables lower temperatures to beused in the initial forming stage and moreover enables the actualpressure difference used to be adjusted to suit the requirements of theextensible material being deformed in a way which is not significantlypossible with vacuum techniques. In addition since the fluid pressure ispositively applied on the side away from any mould used a very evendistribution of pressure over the whole area being deformed can beachieved.

We claim:

1. A method of making a shaped upper component for a shoe whichcomprises deforming an initially flat sheet material by conforming to amoulding surface having a preformed shape for said component, saidpreformed shape being substantially the same as that which would bearrived at by making a shell of resiliently flexible material in theshape of the last corresponding to the desired upper and partiallyflattening out said shell by outwardly displacing opposite side portionsthereof, said preformed shape being such that said upper component isconvertible from the preformed shape to a shoe upper shape by turningthe component inside out and then essentially merely bending thecomponent, the sheet being held during the deformation whereby thedeformation involves stretching of the sheet material; and convertingthe deformed material to the shoe upper shape essentially by turning theshaped upper component inside out and then essentially merely bendingthe component prior to assembly into the shoe.

2. A method of making a shaped upper component for a shoe as claimed inclaim 1, which comprises applying a fluid pressure difference across asheet of extensible upper material, the pressure on at least one side ofthe sheet being in excess of atmospheric pressure, whereby at leastcertain areas of the sheet undergo at least "temporary deformation suchthat said deformed sheet on the pressure being removed possesses thepreformed shape.

3. A method as claimed in claim 2, wherein the pressure difference isapplied by applying an initially quite high deforming pressure followedby a lower pressure sustained for a longer period of time.

4. A method as claimed in claim 3, wherein the initial pressure is inthe nature of a pulse of at least multiples of ms of p.s.i.

5. A method as claimed in claim 1, wherein the preformed shape includesthe vamp and is such that in the region of the vamp point the distancebetween two points at the feather edge on opposite sides of thelongitudinal axis of the preformed shape is not more than about 35percent greater when measured along the surface of the preformed shapethan when measured along a straight line between the two points, bothmeasurements being along lines at right angles to the longitudinal axisof the preformed shape.

6. A method as claimed in claim 1, wherein the sheet material isconformed to the surface of a male mould which itself is characterizedsuch as to impart at least a surface finish to the said surface of theupper material.

7. A method as claimed in claim 6, wherein the characterization of thesurface of the mould is such as to impart a decoration to that surfaceof the upper material which is to be the outer surface of the upper.

8. A method as claimed in claim 1, wherein the sheet material isconformed to a female mould and the surface of the sheet which will beinside the shoe is presented to the mould.

9. A method as claimed in claim 1, wherein the sheet is conformed to amould provided at its edges with a divergent portion such as to define aturn in portion and feather edge for the eventual shaped uppercomponent, whereby on turning the preformed shape inside out are-entrant turn in portion is provided.

10. A method as claimed in claim 1, wherein the surface of the mould isafforded by a release lining.

11. A method as claimed in claim 1, which comprises at least partiallycutting the material around the periphery of the preformed shape priorto removal from the mould.

12. A method as claimed in claim 1, wherein the material is held byclamping means which also afford cutting means for at least preparingthe preformed shape for severance from the sheet.

13. A method as claimed in claim 12, wherein the cutting means comprisea heatable knife edge effective 7 at clamping pressure only to cut thesheet material.

when heated and the cutting means are heated after the material has beenconformed to the preformed shape, for a temperature and time such as toonly partially sever the preformed shape from the sheet so that thepreformed shape can be removed from the mould with the sheet and besubsequently torn from the sheet without itself being damaged.

14. A method of making a shaped upper component for a shoe whichcomprises deformation of an initially flat sheet of material to amoulding surface having a preformed shape for said component, saidpreformed shape being substantially the same as that which would bearrived at by making a shell of resiliently flexible material in theshape of the last corresponding to the desired upper and partiallyflattening out said shell by outwardly displacing opposite side portionsthereof, said preformed shape being such that said upper component isconvertible from the preformed shape to a shoe upper shape essentiallymerely by bending, the

sheet being held during the deformation whereby the' deformationinvolves stretching of the sheet material, the deformation being carriedout with that surface of the sheet material which is to be the outersurface of the upper presented to said moulding surface and saidmoulding surface being itself characterized such as to impart at least asurface finish to the said surface of the upper material; and thereafterconverting the upper component from the preformed shape to the shoeupper shape essentially by bending.

15. A method as claimed in claim 14, in which shoe components providedwithheat or pressure activateable adhesives are located in the desiredposition on a surface of the sheet so that during the deformationprocess they are pressed against the respective surfaces of the sheetthe adhesive being chosen to be such as to effectively secure thecomponents to the sheet material during the deforming operation.

upper presented to said moulding surface.

18 A method according to claim 1, wherein said moulding surface isfemale, said deforming being car ried out with that surface of saidsheet which is to be the inside surface of the upper presented towardssaid moulding surface.

1. A method of making a shaped upper component for a shoe whichcomprises deforming an initially flat sheet material by conforming to amoulding surface having a preformed shape for said component, saidpreformed shape being substantially the same as that which would bearrived at by makiNg a shell of resiliently flexible material in theshape of the last corresponding to the desired upper and partiallyflattening out said shell by outwardly displacing opposite side portionsthereof, said preformed shape being such that said upper component isconvertible from the preformed shape to a shoe upper shape by turningthe component inside out and then essentially merely bending thecomponent, the sheet being held during the deformation whereby thedeformation involves stretching of the sheet material; and convertingthe deformed material to the shoe upper shape essentially by turning theshaped upper component inside out and then essentially merely bendingthe component prior to assembly into the shoe.
 2. A method of making ashaped upper component for a shoe as claimed in claim 1, which comprisesapplying a fluid pressure difference across a sheet of extensible uppermaterial, the pressure on at least one side of the sheet being in excessof atmospheric pressure, whereby at least certain areas of the sheetundergo at least temporary deformation such that said deformed sheet onthe pressure being removed possesses the preformed shape.
 3. A method asclaimed in claim 2, wherein the pressure difference is applied byapplying an initially quite high deforming pressure followed by a lowerpressure sustained for a longer period of time.
 4. A method as claimedin claim 3, wherein the initial pressure is in the nature of a pulse ofat least multiples of 10''s of p.s.i.
 5. A method as claimed in claim 1,wherein the preformed shape includes the vamp and is such that in theregion of the vamp point the distance between two points at the featheredge on opposite sides of the longitudinal axis of the preformed shapeis not more than about 35 percent greater when measured along thesurface of the preformed shape than when measured along a straight linebetween the two points, both measurements being along lines at rightangles to the longitudinal axis of the preformed shape.
 6. A method asclaimed in claim 1, wherein the sheet material is conformed to thesurface of a male mould which itself is characterized such as to impartat least a surface finish to the said surface of the upper material. 7.A method as claimed in claim 6, wherein the characterization of thesurface of the mould is such as to impart a decoration to that surfaceof the upper material which is to be the outer surface of the upper. 8.A method as claimed in claim 1, wherein the sheet material is conformedto a female mould and the surface of the sheet which will be inside theshoe is presented to the mould.
 9. A method as claimed in claim 1,wherein the sheet is conformed to a mould provided at its edges with adivergent portion such as to define a turn in portion and feather edgefor the eventual shaped upper component, whereby on turning thepreformed shape inside out a re-entrant turn in portion is provided. 10.A method as claimed in claim 1, wherein the surface of the mould isafforded by a release lining.
 11. A method as claimed in claim 1, whichcomprises at least partially cutting the material around the peripheryof the preformed shape prior to removal from the mould.
 12. A method asclaimed in claim 1, wherein the material is held by clamping means whichalso afford cutting means for at least preparing the preformed shape forseverance from the sheet.
 13. A method as claimed in claim 12, whereinthe cutting means comprise a heatable knife edge effective at clampingpressure only to cut the sheet material when heated and the cuttingmeans are heated after the material has been conformed to the preformedshape, for a temperature and time such as to only partially sever thepreformed shape from the sheet so that the preformed shape can beremoved from the mould with the sheet and be subsequently torn from thesheet without itself being damaged.
 14. A method of making a shapedupper component for a shoe which comprises deformation of an initiallyflaT sheet of material to a moulding surface having a preformed shapefor said component, said preformed shape being substantially the same asthat which would be arrived at by making a shell of resiliently flexiblematerial in the shape of the last corresponding to the desired upper andpartially flattening out said shell by outwardly displacing oppositeside portions thereof, said preformed shape being such that said uppercomponent is convertible from the preformed shape to a shoe upper shapeessentially merely by bending, the sheet being held during thedeformation whereby the deformation involves stretching of the sheetmaterial, the deformation being carried out with that surface of thesheet material which is to be the outer surface of the upper presentedto said moulding surface and said moulding surface being itselfcharacterized such as to impart at least a surface finish to the saidsurface of the upper material; and thereafter converting the uppercomponent from the preformed shape to the shoe upper shape essentiallyby bending.
 15. A method as claimed in claim 14, in which shoecomponents provided with heat or pressure activateable adhesives arelocated in the desired position on a surface of the sheet so that duringthe deformation process they are pressed against the respective surfacesof the sheet the adhesive being chosen to be such as to effectivelysecure the components to the sheet material during the deformingoperation.
 16. A method as claimed in claim 14, wherein the mould isprovided at its edges with a re-entrant portion such as to define a turnin portion and feather edge for the eventual shaped upper component. 17.A method according to claim 1, wherein said moulding surface is a malemoulding surface and wherein the deforming is carried out with thatsurface of the sheet which is to be the outside surface of the upperpresented to said moulding surface. 18 A method according to claim 1,wherein said moulding surface is female, said deforming being carriedout with that surface of said sheet which is to be the inside surface ofthe upper presented towards said moulding surface.